ES2202337T3 - DATA SUPPORT WITH OPTICALLY VARIABLE ELEMENT. - Google Patents

Abstract

A DATA SUPPORT IS DESCRIBED WITH AN OPTICAL VARIABLE ELEMENT, SHOWING A DIRECTED REFLECTING SURFACE. THE DIRECTED REFLECTING SURFACE IS COMBINED WITH A DIFFUSE CONTROL SURFACE ELEMENT, SO THAT CHARACTERIZATIONS ARE GENERATED. THE DIRECTED REFLECTING SURFACE AND THE SPREADED SURFACE ELEMENT DIFFUSED IS PROVIDED IN SUCH A WAY THAT THE INTENSITY OF THE REFLECTED LIGHT DIRECTED AT LEAST IN AN ANGLE AREA OF OBSERVATION IS HIGHER AND AT LEAST IN ANOTHER ANGLE AREA OF OBSERVATION REDUCED THAT THE INTENSITY OF LIGHT, WHICH RADIATES FROM THE SURFACE AREA OF DIFFUSIVE DISPERSION.

Description

Data support with optically element variable.

The present invention relates to a support of data with an optically variable element, which is provided with a layer that reflects the incident light in a directed way and presents characterizations in the form of characters, samples, images or logos

Optically variable elements are known from some decades in different embodiments. Such elements optically variable are used in the most diverse fields, for example, in advertising, in the field of decoration, but also in the field of security, for example, for Authenticity marks of data carriers.

What these elements have in common is that show different optical effects depending on the angle of observation and lighting. These elements are applied on a data carrier, for example, separately as elements optically variable in the form of diffraction gratings, holograms or cinegrams When using holograms for media protection of data, an optically sensitive element can be applied and variable using currently known techniques, however the manufacture of the hologram entails considerable expenses, over Everything for the production of the so-called hologram master (Master). These  expenses can only be reduced, with respect to each individual hologram, if from the standard hologram that has been made a correspondingly high number of transfer holograms Therefore, this technology is only suitable for large series, where costs relatively high to make the pattern can be distributed among a large number of data carriers. By consequently, said technology offers little flexibility in terms of Desires to change the design of the optically variable element.

In EP 0 477 535 A2 the approach of providing optically variable elements, such as holograms, neutral, and provide the surface with a support data in some areas of a rough structure, which, when applied the optically variable elements are recorded in them, destroying the reflective shine of the metal layer. The structural modifications, which have been made on the surface of data support, serve to individualize by means of a Additional information applied holograms.

In patent application EP 0 420 261 A1, propose different measures to individualize holograms, the degree of individualization being adapted to the aspects of respective security, without substantially losing the advantages Economic series production of standard holograms. The individualization measures are carried out alternately during different phases of the production or preparation of recorded holograms or data carriers equipped with same. Among others, the impression of holograms.

In addition, there are also possibilities to apply an optically variable element on a data carrier by Print.

To protect titles, it is known, for example, by document DE 23 34 702, the constitution of an element optically variable on a security paper by means of a Special gravure printing. In this case, the process of printing is carried out in such a way that on the role of security three-dimensional patterns of lines are formed, which they differ from each other by their height or by their direction, such so when looking at them under a perpendicular angle of incidence or oblique, elements of the image appear or disappear. This way, information on the data carrier can be applied which are only visible under certain viewing angles.

A particularity of these so-called "images latent "is that the information is only visible under certain well-defined viewing angles. For check the information applied to the data carrier, this one must be placed in the correct angular position with respect to the eye to recognize the information. In addition, the elements optically variable, made in this way by printing, they have the disadvantage that they are often only hard recognizable

The aim of the invention is therefore to give to know a data carrier with an optically variable element or create an optically variable element, in which they have entered information, being able to prepare the support of data more economically, being easily recognizable the information entered in the optically variable element under all observation angles, and presenting such information an effect that depends on the angle of observation.

This problem is solved by characteristics indicated in the independent claims. Subsequent developments are the subject of the claims. Dependents

The fundamental idea of the invention consists in the combination of a directed reflection surface with an area diffuse reflection, that is, replace the reflective surface in some parts by a disperser.

When observing the reflective layer under different observation angles, the reflected radiation presents fundamentally different intensities. If the surface of directed reflection is partially replaced by an area of diffuse reflection, then an intensity, substantially constant at all angles of observation and that is produced by diffuse reflection zones, it overlaps the curve of intensity of the reflected radiation that depends on the angle of observation. Depending on the angle of observation, the observer it has, therefore, the feeling that under certain angles the background of the directed reflection surface appears lighter that diffuse reflection zones, while under others angles, diffuse reflection zones appear lighter than the directed reflection surface. When producing information optically perceivable, such as images, logos, characters or similar by combining diffuse reflection zones with areas of directed reflection, an element is obtained optically variable, whose appearance certainly varies under different angles of observation, but whose information content is visible under all viewing angles. Only appearance optics changes from light to dark or from dark to light, creating usually the optical impression of a makeover "positive" to "negative" image. This changing image positive-negative is very pronounced when information is applied in the form of a so-called image of half tone, according to one of the techniques known as, for example, the "Dither" broadcast.

According to a preferred embodiment, the support of data of the invention constitutes an identification document, the which is provided, at least in a partial area, with a layer of diffuse reflection that is coated by a metal layer highly reflective The metal layer is interrupted in areas partial, so that in these places the reflection layer diffuse, which is underneath, becomes visible. Such interruptions of the metal layer have, for example, the shape of characters, samples, images, logos or similar. When observing the surface of the data carrier under a practically perpendicular angle, the interruptions of the metal layer appear clear in front of the bottom Metallic that appears dark. However, by tilting the support of data and when looking at it obliquely, under a certain angle of observation, the maximum intensity of the reflected radiation of shape directed by the metal layer strikes the eye of the observer. The optical impression changes at that angle, so that the irradiation of the metallic bottom overlaps the areas of diffuse reflection, appearing clearer than these.

In this way it arises, under certain angles of observation, the impression of a contrast inversion between foreground and background, which causes positive image change and negative characters or images.

Of the great difference in intensity between the layer of directed reflection and diffuse reflection layer, it is a perfectly recognizable contrast to the naked eye, which also visibly highlights when tilting the data carrier, so that the information is clearly recognizable under all angles of observation.

In addition, the data carrier has a protection excellent against copy reproduction, since the layer reflective needed to produce the latent image can not be produced by copiers, so that the copy is lost The variable optical effect on the copy.

Another advantage results from the fact that, for produce the information, the diffuse reflection layer, which is under the directed reflection layer, it is set to discovered by a laser beam. Through this technology, it is also possible to enter the information in a last operation, even on a card that is otherwise already finished In this way, there is the possibility, on the one hand, of enter individual data in the form of information optically variables in the data carrier and, on the other hand, to attend with a lot of flexibility the desire to change the design.

Other embodiments and advantageous developments of the invention results from the examples, which are explained in continuation by means of schematic figures, in whose representation has consciously dispensed with a reproduction at scale, in order to increase its clarity. The drawings show:

in figure 1, an identity document, according to the invention,

in figure 2, the relative intensity of the rays reflected in a directed way and the reflected rays of diffuse shape depending on the angle of observation,

in figure 3a, an identity document, according to the invention, seen at an angle outside the angle of reflection of the reflective layer,

in figure 3b, the identity document, according to the invention, when looking at the reflection angle of the layer reflector,

in figure 4, a cut through a document of identity, according to the invention,

in figure 5, a cut through another realization of the identity document, according to the invention,

in figure 6, a cut through another realization of the identity document, according to the invention,

in figure 7a, a larger scale detail of the identity document, according to the invention, when looking outside of the reflection angle of the reflective layer, and

in figure 7b, a larger scale detail of the identity document, according to the invention, when looking at the reflection angle of the reflective layer.

Figure 1 shows schematically a data carrier, according to the invention, in the form of a document of identity (1) that is endowed with an optically variable element (two). The optically variable element (2) is applied on the surface (12) of the document as a transfer element, and it comprises a directed reflection layer (3), as well as a brand (4) that has been formed by removing the reflection layer locally addressed (3) in the form of letter "E". By removing the layer of directed reflection (3), an area of diffuse reflection becomes visible underlying. In addition to the optically variable element (2), said document can include on or in one of its layers data of the print format (5), an integrated circuit (15), a band magnetic or other additional elements.

The marks (4) are preferably applied from way they form alphanumeric characters, logos, images, Especially half-tone images, such as the headline photo, data personal or similar.

When you illuminate the document at an angle of fixed incidence \ theta_ {E} with respect to the plane in which find the surface of the document, the incident light is reflected by the directed reflection part (3) of the element optically variable (2) at a solid angle \ theta_ {R} predetermined. By therefore, in the ideal case it cannot be measured or seen, at an angle outside of \ theta_ {R}, any intensity resulting from the reflection in the layer (3).

In daylight, however, the conditions real environmental mean that the light strikes an angle \ theta_ {E} on the data carrier, which is characterized by have maximum intensity, but also cause light to strike dispersed from other directions and with less intensity on the data support, taking place, in this way, a reflection on practically all angles, with maximum intensity at a certain solid angle element? Delta?

Figure 2 shows schematically the evolution of the relative intensity I / I_ {0} for different angles of observation?, which is obtained with a metallic layer of directed reflection of this kind when illuminated under conditions normal environmental The curve (a), which represents the evolution of the intensity for the directed reflection layer (3), has in the angle \ theta_ {R} a pronounced maximum. In the same figure you it also shows, in a similar way, the relative intensity of a diffuse reflection layer, poorly absorbent (b) and a layer of diffuse reflection very absorbent (c). Through the points of intersection of the graphs (a) and (b), an element of solid angle \ Delta \ theta, at which the intensity of the radiation reflected in a directed way is greater than the intensity of diffusedly dispersed radiation

If you look at an optically variable element, which comprises a directed reflection layer and surface elements diffuse reflection, which interrupt this layer, under different viewing angles, surface elements of diffuse reflection will appear light in front of a low dark background Most observation angles. In a range of angles of observation Δ the, however, the intensity portion luminous of diffuse reflection surface elements (4) is clearly surpassed by the light intensity portion of the directed reflection surface (3), so that in said viewing angles a contrast inversion occurs.

Figure 3a shows a detail of the support of data of the invention, according to figure 1. The angle of observation is, in this case, outside the range of angles of observation \ Delta \ theta, so that the letter "E" as a clear emptying (4) inside a metal layer gray (3).

If the document is rotated in this situation so that the angle of observation is within the range of reflection \ Delta \ theta of the metallic reflection layer directed, then the intensity conditions and the "E" empty appears dark in front of a light background. In the Figure 3b shows the same detail of the data carrier at look at it under the angle of reflection \ theta_ {R} of the layer reflective The surface element (4) appears, in this case, dark in front of the light background of directed reflection (3). The information content entered into the element optically variable, in this case in the form of "E", is conserved under all The viewing angles.

Figure 4 shows schematically a possible structure of the data carrier, according to the invention, in a cross section in the area of the element optically variable. Under a transparent coating layer (6) of the document, a metallic layer of directed reflection is arranged (7), which in turn covers a diffuse reflection layer (8), which simultaneously serves as the core of the document. Said core (8) of the document is covered by a second coating layer (9) of the document, which can be transparent or opaque.

With the help of a laser beam, it is removed locally the layer (7) completely, so that the interruptions (10) of the layer shows the diffuse reflection layer (8). In function of the reflective capacity of the layer (7), you can choose a color for the layer (8), which, however, will only absorb parts of the incident light. Less color tones are very suitable absorbents, such as white, yellow, light blue or various known pastel shades. When choosing the properties of the layer (8), it should always be noted that the intensity of the reflection layer directed does not exceed that of the diffuse reflection layer (8) in all observation angles (curve (c), according to figure 2), and otherwise, low contrast inversion will not occur No observation angle. The absorption properties of the layer (8) depend, in this way, on the principle of reflectivity of the layer (7) used, but generally they only have to be chosen poorly absorbent colored layers. The magnitude of absorption that still it is acceptable depends on the reflectivity of the layer of directed reflection (7) overlying.

To constitute the layer (7), they must be considered all materials that reflect the rays directly visible incidents such as metal layers, layers of metallic luster or metal coated layers. In addition, it also they can use those materials that, due to their structure, reflect light rays exclusively or preferably in a certain solid angle element. To this belong, by example, sawtooth profiles or grilles of diffraction that are introduced in layers of any material, or They are well applied on them.

Another embodiment of the data carrier, according to the invention. Under a layer of transparent coating (6), the reflection layer is found directed (7), which is endowed with prints (11) in a color of  diffuse reflection. Under the layer (7), the core (8), which is coated on its back side by a layer back cover (9), which can be transparent or opaque. Said embodiment is advantageous, especially if the data introduced in the optically variable element already apply during the production of said element, or that said data must have a different color from the color of the nucleus (8). Also I know they can also apply several different prints (11) on the surface of the layer (7), which differ from each other also by the coloration To print on the layer (7), finally, the same conditions are valid for the election of print colors such as those already described Previously for layer (8): The print colors chosen they have to disperse the incident light, having to overcome the intensity of scattered light, at least in an angular field, the intensity presented by the metallic reflection layer directed at said angle.

Obviously, data support, according to the invention, can also be produced by modifying the layer of directed reflection in partial areas such that their initial reflection properties are transformed into properties of diffuse reflection. In this case, it has proved very advantageous Matte the metal layer only in certain areas, depending on the desired brand shape, for example, making it rough, so that its reflection properties are lost and that is obtained by therefore, areas in the metal layer that only scatter light, without said layer having to be completely removed in these areas. This procedure can be performed, on the one hand, by the use of burles or mechanical scrapers, which pass through the surface of the metal layer such that it is rough. In addition, you can also remove gloss to the surface by means of a laser beam in low doses, so that the areas irradiated no longer present a directed reflection, although the Metal layer has not been removed in these places. Layered, which produce a directed reflection in a different way, as per example, for the sawtooth pattern mentioned above, it is also possible to cover or fill the structures that provoke directed reflection. In the case of the tooth pattern of saw, you can fill, for example, the depth profile in the layer with a transparent, translucent or opaque color, depending on the shape of the brand, transforming the profile in such a way that in the areas that carry color the directed reflection is replaced by a diffuse reflection.

For some data carriers and procedures of production it may be advantageous that the element optically variable, according to the invention, be applied only on the surface of a data carrier already finished by means of a transfer procedure In this context it can be treated, by example of identity documents, titles, banknotes, passports, passport personalization pages or other documents, whose production cannot be influenced much in their structure. In data carriers of this type, the element optically variable is applied on the surface of the support of data (12). As shown in Figure 6, the element optically variable in this case preferably comprises a adhesive layer (13), a diffuse reflection layer (14), as well as a directed reflection layer (7). Through the procedures of known transfers, such as "Hot Stamping" (heat stamping), it is possible to selectively position and fix optically variable elements of this type on the surface of the data carrier (12), presenting the data carrier (12) in the area where the optically variable element is applied preferably a smooth surface. In those cases where the layer adhesive already meets the requirements, which is required to a layer of diffuse reflection, the layer (14) can also be dispensed with.

If the areas of diffuse reflection become visible by removing the surface of the reflection layer locally directed, then several working methods go into consideration. These include, above all, local disposal of the layer with the help of a laser, the removal of the layer Metallic reflection directed by engraving processes Mechanical or similar. Laser removal has the advantage that the metal layer can also be removed although is inside a laminated compound and that, of this way, the optically variable element can be shaped individually or customized once the production of the full data support. To this end, there are specifically the possibilities to include the personal data of a document of identity, the photograph of the document holder, his printing press digital or similar in the optically variable element. Further, This way of proceeding also offers the possibility of producing individual series if a large number of supports are available of prefabricated data, the series presenting an element optically variable identical as a common characteristic, which can be equipped simply and quickly with the features individual series using a laser.

The size or shape of the element optically variable, to be applied, are not subject to any technical restrictions In this way it is possible, for example, introduce layers of directed reflection inside a card structure, either over the entire surface, or just in partial areas. Also, optically variable elements, which are applied on the surface of a data carrier through a transfer procedure, they can adopt any way, so that they already have an effect, for example, so just for its contour and reflection surface elements fuzzy introduced additionally. The elements optically variables can be entered in the data carrier or applied on its surface, for example, in the form of a circle, star or rectangle, or in any other geometric shape. Further, You can also enter items in the data carrier optically variable ranging from a data carrier edge to another opposite, or that join two adjacent edges.

As can be seen from the extension of a detail of the data carrier, according to the invention, shown in the Figure 7, said data carrier presents, according to another embodiment, a diffuse reflection area (16), in which they have been introduced additional information (17) in the form of samples or characters. In As for its contrast, this information does not differ much diffuse reflection area (16), so that when looking at the data carrier under the angle of reflection \ theta_ {R}, both the diffuse reflection area (16) as well as the information (17) they are irradiated by the directed reflection layer (3), so that, as shown in figure 7b, the element optically variable, when viewed under the angle of reflection \ theta_ {R}, lets the diffuse reflection area (4) appear as a surface dark in front of a light background (7), disappearing the information (17) completely when looking at it from that angle. For to achieve this effect, the information (17) can be entered in the area (16), for example, by printing in one color diffuse reflection, which contrasts only little with that of the area (16). The impression of a color is very suitable for this purpose clear, for example, yellow or light blue, or a pastel shade On a light background, for example, white. But the brands (17) they can also be introduced in the area (16) by local depressions, such as by engraving or laser without color, without another additional color being applied.

Within the framework of the previous examples, the data carrier, according to the invention, can be completed by another variable optical effect For this purpose a hologram is applied on the data carrier, presenting said hologram in one of its upper layers a directed reflection surface, whose reflection direction is determined by flank stiffness of the underlying holographic impression. Since below the directed reflection layer of the hologram is arranged another layer, which has the property of dispersing the incident light rays, if the metal layer is removed, for example, by laser, the effect described by the previous examples can be combined with the optically variable effects of the hologram. In this way, the optically variable marks, already described above, are they allow to enter in the data carrier, being able to regulate the intensity of the laser beam so that they are maintained substantially the optically variable properties of hologram and that the complete hologram information can be superimpose an image that appears positive at certain angles of observation and negative under other angles of observation.

Claims (17)

1. Data support with an optically element variable (2) arranged on it or integrated into it, which presents a surface that reflects the incident light directed towards the observer, and in which the directed reflection surface (3.7) of the optically variable element (2) is combined with an element of diffuse reflection surface (4), such that they form optically recognizable brands and that the reflective capacity of the directed reflection surface (3.7) and the absorption of surface element (4) diffuse reflection are adjusted each other in such a way that the intensity of the reflected light of directed form is, at least in a range of angles of observation, greater than the intensity of the scattered light of the diffuse areas of reflection, and, at least in a range of angles adjacent observation inferior to it, and in which the layer of directed reflection (3.7) presents interruptions (10) and the surface element (8,14) diffuse reflection is located below the directed reflection layer (3.7), the same through interruptions (10). 2. Data carrier according to claim 1, characterized in that the directed reflection layer (3.7) is a metal layer, a metallic gloss layer or a metal coated layer. 3. Data carrier according to claim 1, characterized in that the directed reflection layer (3,7) is provided with a sawtooth profile or a diffraction grating. 4. Data carrier according to claim 1, characterized in that the interruptions (10) are carried out by laser. 5. Data carrier according to claim 1, characterized in that the diffuse reflection surface element has a poorly absorbent color. 6. Data carrier according to claims 1 to 5, characterized in that the diffuse reflection surface element is white, yellow, light blue or pastel in color. 7. Data carrier according to claim 1, characterized in that the diffuse reflection surface element is provided, at least in the area of the interruptions (10), with additional information (17). 8. Data carrier according to claim 7, characterized in that the additional information (17) is present in the form of samples or characters. 9. Data carrier according to one of claims 1 to 8, characterized in that the optically variable element has been applied to the data carrier by means of the transfer procedure. 10. Data carrier according to claim 9, characterized in that the adhesive layer (13) of the optically variable element, transferred, is formed as a diffuse reflection layer with little absorption in the optical spectral zone. 11. Data support with an optically element variable (2) arranged on it or integrated into it, which presents a surface that reflects the incident light directed towards the observer, and in which the directed reflection surface (7) of the optically variable element (2) is combined with an element diffuse reflection surface, such that they form optically recognizable brands and that the reflective capacity of the directed reflection surface (7) and the absorption of the element diffuse reflection surface are adjusted together such so that the intensity of the light reflected in a directed way is, at least in a range of viewing angles, greater than the intensity of light reflected from diffuse reflection areas, and, at least in a margin of adjacent viewing angles, inferior to it, being the reflection surface element diffuse an impression (11) on the directed reflection layer (7). 12. Data carrier according to claim 11, characterized in that the printing (11) is made in a color that is not very absorbent in the optical spectral zone. 13. Data carrier according to claim 11, characterized in that the printing (11) is made in a light color, preferably yellow, light blue or in a pastel color. 14. Data carrier according to claim 11, characterized in that the directed reflection surface has a sawtooth pattern, and that the impression, which forms the diffuse reflection surface element, has been constituted by filling the tooth pattern of saw with a color. 15. Data carrier according to one of claims 11 to 14, characterized in that the optically variable element has been applied to the data carrier by a transfer method. 16. Data carrier according to one of the preceding claims, characterized in that the optically recognizable characterizations form a halftone image. 17. Optically variable element (2), which can be transferred to the surface of a data carrier by transfer procedure and which has a surface (3.7), which reflects the incident light directed towards the observer, and in which the directed reflection surface (3.7) of the optically variable element (2) is combined with a diffuse reflection surface element (4.14), such that optically recognizable marks are formed and that the reflective capacity of the directed reflection surface (3,7) and the absorption of the diffuse reflection surface element (4,14) are adjusted to each other such that the intensity of the light reflected in a directed manner is, at least in one margin of observation angles, greater than the intensity of the reflected light of diffuse reflection areas, and, at least in an adjacent margin of observation angles, less than the same, the reflection surface element being diffuse impression (11)
on the directed reflection layer (7), or that the directed reflection layer (3.7) has interruptions (10), through which the underlying diffuse reflection surface element (14) becomes visible.